sensor_plot_spherical_map

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spherical_map … end_spherical_map

spherical_map

   Stub Definition Commands

   # Sensor Control

   mode_name ...
   automatic_target_cueing ...
   fixed_sensor_position | fixed_target_position
   sensor_platform_altitude ...
   sensor_platform_yaw ...
   sensor_platform_pitch ...
   sensor_platform_roll ...

   # Jammer Control

   jammer_to_signal_reference ...
   jamming_platform_name ...

   target_platform_type
   target_speed
   target_mach
   target_heading
   target_yaw
   target_pitch
   target_roll

   # Target Region

   azimuth_limits ...
   azimuth_step ...
   elevation_limits ...
   elevation_step ...
   range ...
   altitude ...

   # Output selection

   variable ...
   script_variable ...
   detection_reference ...

   pd_map_file ...
   header_line_1 ...
   header_line_2 ...
   header_line_3 ...
   output_column_limit ...

   gnuplot_file ...

end_spherical_map

Overview

The spherical_map command is used to generate a plot file of target detectability at a specified range or altitude over a range of azimuth and elevation viewing angles. Two types of plot files can be produced:

• A ‘pd map’ file for the program ‘sigview’ to show a typical spherical plot.

• A file suitable for plotting with the program ‘gnuplot’.

To create a file, the following process should be followed:

• Define a platform type of the type specified by the command target_platform_type (Default: TARGET_PLATFORM_TYPE) with the desired radar, infrared, optical or acoustic signature depending on the type(s) of sensors being tested.

• Define a platform type of SENSOR_PLATFORM_TYPE which contains the sensor to be used to detect the target.

• Define the spherical_map input block with:

  • range, altitude, azimuth_limits and elevation_limits (and optionally azimuth_step and elevation_step commands to define the spherical mesh of sample points.

  • An optional target_speed command to specify the target speed.

  • Output selection commands.

Sensor Control

mode_name <mode_name>

Specifies the name of the mode to be used if the sensor is a multi-mode sensor.

Default The default mode of the sensor. This will be the value of the initial_mode command of the sensor (if defined) or the first mode (if initial_mode was not defined).

automatic_target_cueing <boolean-value>

If ‘true’, the sensor will be cued to point at the target when performing a detection chance. If ‘false’, the sensor will be remain in its initial condition.

Default true (The sensor will always be cued to point at the target)

fixed_sensor_position

fixed_target_position

Defines which object is held at a constant location at the center of the sample sphere, while the other object is moved over the sample sphere.

• fixed_sensor_position means the sensor is fixed at the center of the sample sphere while the target is moved over the sample sphere.

• fixed_target_position means the target is fixed at the center of the sample sphere while the sensor is moved over the sample sphere.

Default fixed_sensor_position

sensor_platform_altitude <length-value>

Specify the altitude of the sensing platform.

Default 0 meters

sensor_platform_yaw <angle-value>

sensor_platform_pitch <angle-value>

sensor_platform_roll <angle-value>

Specify the orientation of the sensing platform with respect to the direction of flight. The yaw angle is added to the heading and the pitch and roll angles are used directly as specified. This is useful for examining sensor coverage when the platform is flying in some other condition other than straight-and-level.

Default 0 degrees for all angles

Jammer Control

jammer_to_signal_reference <db-ratio-value>

Specifies the jammer-to-signal (J/S) reference to be used when plotting the ‘required_jamming_power’ variable.

Default 0.0 db

jamming_platform_name <platform-name>

Specifies the platform that will be used to calculate the required jamming power. This input is to be used when plotting the ‘required_jamming_power’ variable for the location of the jammer system.

Default TARGET_PLATFORM_TYPE

target_platform_type <target-platform-type>

Specify the platform type to be used to represent the target.

Default TARGET_PLATFORM_TYPE

target_speed <speed-value>

target_mach <real-value>

Specify the speed at which the target is to be considered moving. This is only used if the sensor needs to performs Doppler processing. The speed may be specified using either an absolute speed (target_speed) or a Mach number (target_mach). If both are specified the last value takes precedence.

Default target_speed 250 m/s

target_heading <angle-value>

Specifies the heading at which the target will be placed.

Default If not specified, the target will be oriented at each grid point to point at the sensor.

target_yaw <angle-value>

Specify the yaw angle with respect to the target heading at which the target will be placed. This is primarily used for certain types of infrared sensor plots where it desired to hold the sensor-to-target viewing angle a constant. In those cases the target_heading will be omitted and the value of this command will be set to the desired sensor-to-target viewing angle.

Default 0.0 deg

target_pitch <angle-value>

Specify the pitch angle at which the target will be placed.

Default 0 degrees

target_roll <angle-value>

Specify the roll angle at which the target will be placed.

Default 0 degrees

Target Region

azimuth_limits <min-az-value angle-value> <max-az-value angle-value>

Specifies the azimuth extent of the viewing angle samples.

Default -180 deg 180 deg

azimuth_step <angle-value>

Specifies the angle increment between azimuth samples.

Default 1 deg

elevation_limits <min-el-value angle-value> <max-el-value angle-value>

Specifies the elevation extent of the viewing angle samples.

Default -90 deg 90 deg

elevation_step <angle-value>

Specifies the angle increment between elevation samples.

Default 1 deg

range <length-value>

Specifies the range to the sample point.

Note

If specified the range will be fixed to this value and the altitude input will not be used.

altitude <length-value>

Specifies the altitude to the sample point.

Note

If specified the target altitude will be fixed to this value and the range input will not be used.

Output Selection

variable <variable-name>

<variable-name>	Description	Notes
pd	The probability of detection.	If multiple sensors are provided, the result will be the maximum probability of detection by any sensor.
detection_threshold	The detection threshold in dB.	If multiple sensors are provided, the result will be the minimum detection threshold by any sensor. For WSF_ESM_SENSOR types the detection threshold is only valid when a successful interaction happens between the transmitter and receiver.
required_rcs**or **rcs_required	The radar cross section required for the sensor to detect the target in dBsm.	If multiple sensors are provided the result will be the minimum value determined for any sensor. Selecting this may also require the specification of detection_reference
required_jamming_power or jamming_power_required or required_jammer_power or jammer_power_required	The jamming power required to overcome the target signal by in dBsm.	If multiple sensors are provided the result will be the maximum value determined for any sensor. Selecting this may also require the specification of jammer_to_signal_reference.
radar_signature	The radar signature of the target presented to the sensor in dBsm.	If multiple sensors are provided, the result will be the maximum value presented to any sensor.
optical_signature	The optical signature of the target presented to the sensor in dB.	If multiple sensors are provided, the result will be the maximum value presented to any sensor.
infrared_signature	The infrared signal of the target presented to the sensor in w/sr.	If multiple sensors are provided, the result will be the maximum value presented to any sensor.
signal_power	The received signal power in dBW.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
clutter_power	The received clutter power in dBW.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
noise_power	The receiver noise power in dBW.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
jammer_power	The received jammer power, to include noise and pulsed-noise, in dBW.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
noise_jammer_power	The received noise only jammer power in dBW.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
pulse_jammer_power	The received non-coherent pulse (pulsed noise) jammer power in dBW.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
coherent_jammer_power	The received coherent (coherent pulse and false-target) jammer power in dBW.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
jammer_to_mds	The jammer (noise and pulsed noise) to minimum detectable signal (detection_threshold + noise_power) in dB.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
jammer_to_signal	The jammer (noise and pulsed noise) to signal ratio in dB.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
noise_jammer_to_signal	The jammer (noise power only) to signal ratio in dB.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
pulse_jammer_to_signal	The jammer (pulsed noise power only) to signal ratio in dB.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
coherent_jammer_to_signal	The jammer (coherent jammer power only) to signal ratio in dB.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
coherent_jammer_to_noise	The jammer (coherent jammer power only) to receiver noise power in dB.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
signal_to_noise	The signal to noise ratio in dB. Only the receiver thermal noise is accounted for.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
signal_to_interference	The signal to interference ratio in dB.	Includes the interference power due to receiver thermal noise, clutter, and jamming (if present). If multiple sensors are provided, the result will be the maximum value seen to any sensor.
signal_at_target	The signal power density present at the target in dBW/m^2.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
background_radiant_intensity	The background radiant intensity as seen by the sensor.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
contrast_radiant_intensity	The contrast radiant intensity as seen by the sensor.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
attenuation_factor	The atmospheric attenuation factor of the signal as seen by the sensor in dB.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
propagation_factor	The propagation factor of the signal as seen by the sensor in dB.	If multiple sensors are provided, the result will be the maximum value seen to any sensor.
transmit_antenna_gain	The transmit antenna gain in dB.	If multiple sensors are provided, the result will be the maximum value for any sensor.
receive_antenna_gain	The receive antenna gain in dB.	If multiple sensors are provided, the result will be the maximum value for any sensor.
transmit_gain_propagation_factor	The transmit antenna gain multiplied by the one-way propagation factor, in dB.	If multiple sensors are provided, the result will be the maximum value for any sensor. This variable is only valid for monostatic radars.
receive_gain_propagation_factor	The receive antenna gain multiplied by the one-way propagation factor, in dB.	If multiple sensors are provided, the result will be the maximum value for any sensor. This variable is only valid for monostatic radars.
slant_range	The slant range from the sensor to the target in meters.	If multiple sensors are provided, the result will be maximum the value seen to any sensor.
ground_range	The ground range from the sensor to the target in meters.	If multiple sensors are provided, the result will be the value seen by the last sensor processed, since this variable is only applicable to single-sensor plots.
azimuth_angle	The azimuth angle from the sensor to the target in degrees.	If multiple sensors are provided, the result will be the value seen by the last sensor processed, since this variable is only applicable to single-sensor plots.
elevation_angle	The elevation angle from the sensor to the target in degrees.	If multiple sensors are provided, the result will be the value seen by the last sensor processed, since this variable is only applicable to single-sensor plots.
angle	The angle between the sensor boresight and the beam center.	This is typically used to deterimine the beam steering angle for electronically scanned sensor. If multiple sensors are provided, the result will be the value seen by the last sensor processed, since this variable is only applicable to single-sensor plots.
grazing_angle	The angle between the sensor antenna location (NOT boresight) to the target in degrees.	If multiple sensors are provided, the result will be the value seen by the last sensor processed, since this variable is only applicable to single-sensor plots.
target_to_sensor_slant_range	The slant range from the target to the sensor in meters.	If multiple sensors are provided, the result will be maximum the value seen to any sensor.
target_to_sensor_ground_range	The ground range from the target to the sensor in meters.	If multiple sensors are provided, the result will be the value seen by the last sensor processed, since this variable is only applicable to single-sensor plots.
target_to_sensor_azimuth_angle	The azimuth angle from the target to the sensor in degrees.	If multiple sensors are provided, the result will be the value seen by the last sensor processed, since this variable is only applicable to single-sensor plots.
target_to_sensor_elevation_angle	The elevation angle from the target to the sensor in degrees.	If multiple sensors are provided, the result will be the value seen by the last sensor processed, since this variable is only applicable to single-sensor plots.
sensor_latitude	The latitude of the sensor platform in decimal degrees.
sensor_longitude	The longitude of the sensor platform in decimal degrees.
sensor_altitude	The altitude of the sensor platform in meters.
sensor_speed	The speed of the sensor platform in meters/second.
sensor_heading	The heading of the sensor platform measured clockwise from north.
sensor_pitch	The pitch angle of the sensor platform in degrees.
sensor_roll	The roll angle of the sensor platform in degrees.
target_latitude	The latitude of the target in platform decimal degrees.
target_longitude	The longitude of the target in platform decimal degrees.
target_altitude	The altitude of the target platform in meters.
target_speed	The speed of the target platform in meters/second.
target_heading	The heading of the target platform measured clockwise from north.
target_pitch	The pitch angle of the platform target in degrees.
target_roll	The roll angle of the platform target in degrees.
sar_dwell_time	The dwell time (in seconds) needed to produce an image of the desired resolution specified in the sensor definition.	The sensor being tested must be of type WSF_SAR_SENSOR.
sar_resolution	The resolution (in meters) of an image that can be produced with the dwell time specified in the sensor definition.	The sensor being tested must be of type WSF_SAR_SENSOR.
sar_clutter_to_noise	The SAR clutter-to-noise ratio (in dB).	The sensor being tested must be of type WSF_SAR_SENSOR.
sar_doppler_foldover	The difference between the PRF and the minimum PRF that could be used without causing ‘doppler foldover’.	The sensor being tested must be of type WSF_SAR_SENSOR.
pixel_count	The number of pixels the target occupies in the image.	Available for WSF_EOIR_SENSOR and WSF_SAR_SENSOR.
masking_status	The masking status at the point.	The value will be 0 if the target is not masked, 1 if masked by the horizon and 2 if masked by the terrain.
terrain_elevation	The terrain elevation in meters.	Use with horizontal_map.

script_variable <variable/script-name>

Specify the name of the ‘global’ script variable to use to derive and manipulate a variable from the sensor detection attempt interaction result.

Note

The script must have a ‘double’ as the return type and have inputs in the format and order of ‘WsfPlatform , WsfSensor , WsfPlatform , WsfSensorInteraction’.

Note

The script must be defined globally, i.e. outside any platforms or the sensor_plot mapping blocks.

Note

If multiple sensors are provided, the result will be the maximum value presented to any sensor.

Example script that writes out the Jammer/MDS, need to include script_variable jammer_to_mds also to run the script:

script double jammer_to_mds(WsfPlatform aPlatform, WsfSensor aSensor, WsfPlatform aTarget, WsfSensorInteraction aResult)
   if ((aResult.DetectionThreshold() > -300.0) &&
       (aResult.RcvrNoise() > -300.0) &&
       (aResult.NoiseJammerPower() > -300.0) &&
       (aResult.NoiseJammerPower() != 0.0))
   {
      double MDS =  aResult.DetectionThreshold() + aResult.RcvrNoise();
      return aResult.NoiseJammerPower() - MDS;
   }
   return -300.0;  // default value in dB
end_script

detection_reference <db-ratio-value>

The reference signal-to-noise ratio used to determine the required_rcs or rcs_required variable.

Default 12.8 dB

pd_map_file <file-name>

Specifies the name of the file to which ‘pd map’ output will be written. The name does not imply that only pd can be written, but rather denotes a common file format.

Default ‘pd map’ output will not be produced.

header_line_1 <text>

header_line_2 <text>

header_line_3 <text>

Specifies the text to be contained in the first three lines of the output file when pd_map_file is specified.

Default all header lines are blank.

output_column_limit <integer>

Specifies the maximum number of columns per physical line in the output file when pd_map_file is specified.

Default 100

Note

If the file is to be imported into a spreadsheet such as Microsoft Excel, this value should be set so that the rows do not have to be split into multiple physical lines.

gnuplot_file <file-name>

Specifies the name of the file to which ‘gnuplot’ output will be written.

Default ‘gnuplot’ output will not be produced.